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  <title>Document</title>
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  <script>
    // 1.数组初始化
    let arr = [2, 6, 18, 15, 40]
    let sum = 0
    // 2.通过for循环 if判断得出结果
    for (let i = 0; i < arr.length; i++) {
      // 被3整除的偶数的和
      if (arr[i] % 3 == 0 && arr[i] % 2 == 0) {
        sum += arr[i]
      }
    }
    alert(`${sum}`)
  </script>
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